عنوان مقاله [English]
Several researches have been carried out on seismic behavior and retrofitting of unreinforced masonry (URM) walls. Using an external retrofitting surface layer is the most popular strengthening technique for URM walls. Recently, using fiber reinforced concrete (FRC) overlay as a strengthening technique for URM walls is evaluated though a series of experimental studies. Therefore, in this paper finite element modeling of URM walls strengthened with FRC layer under in-plane actions is considered through a micro modeling approach in finite element software ABAQUS. Concrete Damage Plasticity Model is used for modeling of brick unites and mortar joints. In this article the finite element modeling of the retrofitted walls is explained and is verified with results of a previous experimental study. Results obtained from analyzes show that the finite element model can simulate the in-plane behavior of strengthened URM walls well. In addition, a parametric study is performed and the influence of some parameters such as FRC surface layer thickness, fiber content and retrofitted face of the panel on the in-plane capacity of the strengthened masonry panels is evaluated. Analysis results show that the FRC overlay thickness and retrofitted face of the wall has considerable effects on the in-plane strength of retrofitted URM walls.
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